Swordfish Wiki | SwordfishUser / EthernetSNTP

This sample program uses the SNTP protocol to obtain the time and date from a remote time server. The time and date returned is encoded, so we use the utility module "UTCDateTime.bas" to decode the returned value. Here's what you need to do.

Plug a network cable into your board and connect to your network. For example, just plug your Ethernet board into your broadband router, which will act as a DHCP server.
Compile and then program the code into your device.
Start the Swordfish Serial Communicator plugin, and a connect to your MCUs USART at 115200 baud.
Reset the MCU.

If all goes well, something like the following should be displayed in the Serial Communicator window

 Waiting for DHCP...
 Host Name     : SWORDFISH      
 MAC Address   : $00 $04 $A3 $00 $00 $00 
 IP address    : 192.123.223.1
 Mask          : 255.255.255.0
 Gateway       : 192.123.223.254
 Primary DNS   : 192.123.223.254
 Secondary DNS : 158.123.223.58
 Enter 't' to display UTC time

Now all you need to do is enter "t" and press enter. The value returned will look something like this

 Wed 06/02/2008 09:00:31

An interesting feature of the Swordfish SNTP (time server) module is that is does not repeatedly interrogate a time server for information. Instead, the PIC uses and internal millisecond counter and polls the time server every ten minutes or so to resynchronise.

Sample Code

// device and clock - code will work on an 18F452 as well...
Device = 18F4680
Clock = 20

// important configurations...
#option ENC28J60_CS = PORTD.6
#option NET_ICMP = true   // enable ping 
#option NET_DHCP = true   // enable Dynamic Host Configuration Protocol (DHCP)
#option NET_NBNS = true   // enable NETBIOS
#option NET_SNTP = true   // enable time server
Include "NETApp.bas"      // always first!

// TCPIP stack specifics...
Include "NETTypes.bas"
Include "SNTP.bas"

// program helpers...
Include "NETAppDisplay.bas"
Include "usart.bas"
Include "convert.bas"
Include "UTCDateTime.bas"
{
****************************************************************************
* Name    : UTCTime                                                        *
* Purpose : Gets the UTC time and formats the output to                    *
*         : DayOfWeek DAY MONTH YEAR HOUR:MINS:SECS                        *
****************************************************************************
}
Function UTCTime() As String(24)
   Dim Seconds As DWORD
   Seconds = SNTPGetUTCSeconds
   UTC.Decode(Seconds)
   result = UTC.DayOfWeek(DateTime.DOW) + " " + 
            DecToStr(DateTime.Day,2) + "/" + DecToStr(DateTime.Month,2) + "/" + DecToStr(DateTime.Year) + " " + 
            DecToStr(DateTime.Hour,2) + ":" + DecToStr(DateTime.Min,2) + ":" + DecToStr(DateTime.Sec,2)
End Function

// program start...
SetBaudrate(br115200)

#if NET_DHCP
Write("Waiting for DHCP...",13,10)
#else
DisplayConfig
USART.Write("Enter 't' to display UTC time",13,10)
#endif

// loop forever...
While true

   // This task performs normal stack task including checking for incoming 
   // packet, type of packet and calling appropriate stack entity to process it.
   NETApp.Task

   // read USART value - if equal to "t" then display UTC time...
   If DataAvailable Then
      If USART.ReadByte = Byte("t") Then
         USART.Write(UTCTime,13,10)
      EndIf
   EndIf

   // If DHCP is enabled, display configuration when a DHCP event
   // has occurred...
   #if NET_DHCP
   If NETApp.DHCPEvent() Then
      DisplayConfig()
      USART.Write("Enter 't' to display UTC time",13,10)
   EndIf
   #endif
Wend

From Swordfish Wiki

SwordfishUser: EthernetSNTP

Sample Code